In addition to § 15.2-2244, a locality may include in its subdivision ordinance provisions permitting a single division of a lot or parcel for the purpose of sale or gift to a member of the immediate family, as defined in § 15.2-2244, of the property owner, if (i) the property has been owned for at least 15 consecutive years by the current owner or member of the immediate family and (ii) the property owner agrees to place a restrictive covenant on the subdivided property that would prohibit the transfer of the property to a nonmember of the immediate family for a period of 15 years. Notwithstanding the provisions of clause (ii), a locality may reduce or provide exceptions to the period of years prescribed in such clause when changed circumstances so require. Upon such modification of a restrictive covenant, a locality shall execute a writing reflecting such modification, which writing shall be recorded in accordance with § 17.1-227. The locality may require that the subdivided lot is no more than one acre and otherwise meets any other express requirement contained in the Code of Virginia or imposed by the local governing body.